Introduction

This Method of Procedure (MOP) describes the steps to downgrade the OAM and its managed VMs in an OpenStack Environment from the upgraded version to the desired base version.

Prerequisites

This section lists the prerequisites for performing the OAM downgrade:

  • Ensure the OAM and managed nodes are up and running.
  • Ensure the EMS node is accessible.
  • Ensure the EMS includes a lower version of the config with it. Ensure the version is the same as the version in which the OAM will be downgraded.
  • Ensure the SBC image is glanced.

Procedure

  1. Log on to the EMS GUI.

  2. Navigate to Network → Cluster Management. 

    Cluster Management

  3. Select the cluster that contains the nodes which you need to downgrade.

  4. Navigate to Configuration History.

  5. From the table, select the revision that contains the same version as the software version to which the node will be downgraded.

  6. Click Restore. 

    See the example below, which shows the cluster configuration history of upgrading from 08.02.02R000 to 10.00.00R000, and then downgrading back to 08.02.02R000.

    Configuration History Example

    Note

    With SBC 10.00.00R00, select any 8.02.02R000 revision (In this scenario, there are three revisions available as 1,2, and 3).
    Consider revision 3 is restored. The OAM will download this revision and push back a new revision (revision 7 in the scenario of version 08.02.02R000).

    Auto-reboot of nodes does not work. The user after validating that the active revision in the cluster is the same as the lower version in which the downgrade is expected to perform.

  7. Perform downgrade of OAM and nodes by stack delete and create method.
  8. Once the new nodes are up, log on to the EMS and validate a new revision contains a version of the new SBC image.